tasyncclosestall.nim still flaky test: Address already in use

[timotheecour]

as #12918 shows, tasyncclosestall.nim is still a flaky test

Example

see CI failure for #12918

Current Output

PASS: tests/async/tasyncawait_cyclebreaker.nim C                   ( 6.39586997 secs)
FAIL: tests/async/tasyncclosestall.nim C
Test "tests/async/tasyncclosestall.nim" in category "async"
Failure: reExitcodesDiffer
Expected:
exitcode: 0

Gotten:
exitcode: 1

Output:
tasyncclosestall.nim(99) tasyncclosestall
asyncmacro.nim(313)      server
asyncmacro.nim(34)       serverNimAsyncContinue
tasyncclosestall.nim(87) serverIter
asyncnet.nim(632)        bindAddr
oserr.nim(94)            raiseOSError
[[reraised from:
tasyncclosestall.nim(99) tasyncclosestall
asyncdispatch.nim(1884)  waitFor
asyncfutures.nim(383)    read
]]
Error: unhandled exception: Address already in use
Async traceback:
  tasyncclosestall.nim(99) tasyncclosestall
  asyncmacro.nim(313)      server
  asyncmacro.nim(34)       serverNimAsyncContinue
    ## Resumes an async procedure
  tasyncclosestall.nim(87) serverIter
  asyncnet.nim(632)        bindAddr
  oserr.nim(94)            raiseOSError
Exception message: Address already in use
Exception type: [OSError]

PASS: tests/async/tasyncconnect.nim C                              ( 2.38197374 secs)

Expected Output

works

Additional Information

this test previously had surgery #12744

This test is very flaky, this change might help reducing the

but is still flaky (perhaps with a different error msg)